The present invention relates to a screw compressor and a method of manufacturing a rotor for the screw compressor, and particularly to an oil-cooled screw compressor with no timing gear, of which performance is improved while ensuring reliability of a tooth surface of the rotor.
In a conventional oil-cooled screw compressor, it is general to connect a male rotor to a shaft of a drive motor directly or via a coupling so that the male rotor operates as a driving shaft to rotate a female rotor. Also, in order to construct the male and female rotors, the number of teeth of the male rotor is smaller than that of the female rotor in view of a geometrical aspect. Further, cast metal such as ductile iron are machined to be used as a material for the rotors.